# @gadget/ai

Gadget Code's AI API abstraction layer. Provides a single internal API contract for calling AI providers (Ollama, OpenAI) without consumer code knowing which provider is configured.

## Principles

1. **One interface, all providers.** Consumer code calls `createAiApi()` once and holds the resulting `AiApi`. It never checks `provider.sdk` again.
2. **All AI SDK knowledge is contained here.** No consumer imports `ollama` or `openai` SDKs directly.
3. **Responses are normalized.** All provider responses are translated to Gadget Code's internal interface types before returning.

## Usage

```typescript
import { createAiApi } from "@gadget/ai";

const provider = {
  _id: "local-ollama",
  name: "Local Ollama",
  sdk: "ollama",
  baseUrl: "http://localhost:11434",
  apiKey: "",
};

const modelConfig = {
  provider,
  modelId: "llama3.2",
  params: {
    reasoning: false,
    temperature: 0.8,
    topP: 0.9,
    topK: 40,
  },
};

const ai = createAiApi(provider, logger);

const result = await ai.generate(modelConfig, {
  prompt: "Explain what this code does",
  systemPrompt: "You are a code reviewer.",
});
console.log(result.response);
console.log(result.stats.duration.text); // formatted, e.g. "00:00:02"
```

## API

### Factory

**`createAiApi(provider, logger?)`** — Returns an `AiApi` instance for the given provider. `logger` is optional and defaults to a no-op logger. Pass your own logger to receive debug output.

### AiApi

Abstract base class. Currently implemented:

- **`OllamaAiApi`** — Ollama provider
- **`OpenAiApi`** — OpenAI provider (stubbed)

#### `ai.generate(model, options, streamCallback?)`

Single-prompt generation. Returns `IAiGenerateResponse`.

#### `ai.chat(model, options, streamCallback?)`

Chat with conversation history. Pass `options.context` for multi-turn对话. Returns `IAiChatResponse`.

### Interfaces

All interfaces are exported for use by consumers:

- **`IAiProvider`** — AI provider configuration
- **`IAiModelConfig`** — Model + runtime parameters
- **`IAiGenerateOptions`** / **`IAiGenerateResponse`**
- **`IAiChatOptions`** / **`IAiChatResponse`** — includes `tool_calls` for function-calling models
- **`IAiInferenceStats`** — token counts and duration (both raw `seconds` number and formatted `text` string)
- **`IAiLogger`** — injectable logger interface (`debug`, `info`, `warn`, `error`)

## Providers

### Ollama

Configured via `IAiProvider` with `sdk: "ollama"`. Uses the `ollama` npm package. Handles streaming responses and normalizes Ollama-specific response fields (thinking tokens, token counts, duration).

### OpenAI

Configured via `IAiProvider` with `sdk: "openai"`. Stubbed — `chat()` and `generate()` throw `"Not yet implemented"`. Implement by wiring the `openai` npm package following the same pattern as `OllamaAiApi`.

## Duration Formatting

The library uses `numeral` to provide a consistent formatted duration string (`stats.duration.text`) in `hh:mm:ss` format. The raw nanosecond value is also returned in `stats.duration.seconds` for consumers that need the raw number.

## Adding a New Provider

1. Create `packages/ai/src/<provider>.ts` — extend `AiApi`, implement all abstract methods
2. Update `packages/ai/src/index.ts` — add the new class to the `createAiApi` factory switch
3. Update this README

No consumer code changes required.
